BRUSSELS, Dec 20 (Reuters) - Novavax (NVAX.O) is expected to start delivering its COVID-19 vaccines to the European Union in the first quarter of 2022, an EU source said, as experts for the region"s drug regulator met on Monday to decide whether to approve the shot. The EU Commission had no immediate comment and the U.S. biotech company was not immediately available for comment. The EU source declined to be identified because they were not authorised to speak to the media. If approved, the two-dose vaccine, branded Nuvaxovid, would be the fifth coronavirus shot to be brought on to the EU market and arrives as the Omicron coronavirus variant spreads. Earlier in the year, Novavax had told the European Union it planned to begin making first small shipments of its vaccine for the bloc towards the end of this year, with the bulk of supplies in 2022, an EU official told Reuters in May. read more The EU Commission and the company signed a contract in August for the delivery of up to 200 million doses, of which half is optional.